Inboard-outboard drive



March 4, 1969 K. R. PIKE ETAL 3,430,604

INBOARD-.OUTBOARD DRIVE Filed Jan. 24, 1967 Sheet of 2 March 4, w69 K. R. PIKE ETAL INBOARD-OUTBOARD DRIVE Sheet Filed Jan. 24, 1967 United States Patent O 8 Claims ABSTRACT OF THE DISCLOSURE An inboard-outboard drive assembly for a boat wherein the gear means interconnecting the horizontal drive shaft from the inboard power unit and the vertical drive shaft of the outboard propulsion unit is centered `on the pivotal axis of the propulsion unit so that the pivotal movement of the propulsion unit is accompanied by readjustment of the relative angular positions of the various gears of the interconnecting gear means. Also, an inboard-outboard drive unit which includes a damping -assembly comprising a shaft, an elastomer sleeve member bonded to the shaft, and a socket member receiving the sleeve member with a frictional -sliding fit. The shaft is rotated in response t-o pivotal movement of the propulsion unit `so that the initial upward pivotal movement of the propulsion unit is absorbed by yielding of the elastomer member, whereafter the elastomer member breaks loose within the socket to provide a frictional sliding resistance to further pivotal movement of the propulsion member.

Background of the invention This invention relates to an inboard-outboard drive for a water craft. More particularly, it relates to the mannerin which the horizontal drive shaft of the inboard power unit is drivingly interconnected to the vertical drive shaft of the outboard propulsion unit as well as the manner in which the upward pivotal movement `of the propulsion unit is damped.

Summary of the invention It is a general object of the present invention to provide an improved inboard-outboard drive assembly for a water craft.

A more specific object of the present invention is to provide an improved arrangement for interconnecting the drive shafts of the inboard power unit and the outboard propulsion unit.

Another object is to provide an improved arrangement for dam-ping the upward pivotal movement of the propulsion unit.

Another object is to provide an improved damping lsystem which also functions as a tilting system to voluntarily raise the propulsion unit partially or completely out of the water.

v vThe inboard-outboard drive assembly of the invention is lof the type including a drive shaft extending horizontally from the inboard power unit rearwardly through the transom of the craft and a propulsion unit disposed outboard of the craft and comprising a drive leg normally depending downwardly to position a propeller carried on the lower end of the drive leg in the Water. One aspect of the invention concerns the manner in which the pivotal movement of the propulsion unit is damped. The damping assembly of the invention includes a shaft having an elastomer sleeve member bonded to `one end thereof with the elastomer mem-ber in turn received with a frictionally sliding t in a normally fixed socket member. Means are provided to rotate the shaft in response ICC t-o pivotal movement of the propulsion unit so that the elastic material of the elastomer member yields during the initial upward pivotal movement of the propulsion unit, whereby to provide relatively little resistance to such initial movement, whereafter the elastomer member and socket undergo relative rotation at their frictional interface to provide frictional sliding resistance to further pivotal movement of the propulsion member.

According to another feature of the invention, the means which operate to rotate the damping shaft in response to upward pivotal movement of the propulsion unit also operate in reverse; that is, to pivot the propulsion unit upwardly in response to rotation of the damping shaft. Accordingly, by suitably rotating the socket member, the propulsion unit may be voluntarily raised out of the water for purposes of launching, shallow Water operation, etc.

According to another feature of the invention, the gear means drivingly interconnecting the horizontal drive shaft from the inboard power unit and the vertical drive shaft of the propulsion unit includes a gear member which is mounted for rotation on the pivotal axis of the propulsion unit so that the pivotal movement of the propulsion unit is accompanied by `a readjustment of the relative angular positions of the various gears of the interconnecting gear means without disturbing the meshing engagement of the various gears.

Brief description of the drawings A preferred embodiment of the invention is shown in the accompanying drawings. In the drawings:

FIG. 1 is a cross-sectional view of an inboard-outboard drive assembly embodying features of the present invention; and l FIG. 2 is a fragmentary cross-sectional view taken on line 2-2 of FIG. l.

Detailed description of a preferred embodiment The inboard-outboard drive assembly of the present invention includes an internal combustion engine seen fragmentarily at 10 and adapted to be disposed in the rear portion of a Water craft immediately forwardly of the transom 12, a housing member 14 secured as by bolts 16 to engine 10 and extending through an opening 1'7 in transom 12 to a location outboard of the craft, and a propulsion unit comprising a drive leg 18 suspended from housing 14 in a position outboard of transom 12.

Housing 14 is of cored construction and includes a socket portion 14a receiving a bearing sleeve member 20. Sleeve member 20 accommodates tapered roller bearings 22 and 24 journaling the output shaft 26 of engine 10 Within housing 14. Housing 14 further includes a partition 14b mounting a seal 28 sealingly engaging output shaft 26. A bevel gear 30 is carried on the distal end of drive shaft 26, and a bellows seal 32 is disposed generally within transom opening 17 and extends between transom 12 and housing 14 to provide a water seal therebetween. Seal 32 is fastened to the outer face of transom 12 by a clamping ring 34 and to housing 14 by a clamping ring 36. Housing 14 is bifurcated beyond socket portion 14a to provide a left support arm 14e and a right support arm 14d, as viewed in FIG. 2. Arms 14c and 14d journal a generally horizontal pivot shaft 38.

Drive leg 18 includes an upper housing 40, an intermediate housing 42 and a lower housing 43. Housing 40 defines at its upper end a pair of laterally spaced ears or arms 40a and 40b keyed to horizontal pivot shaft 38. Housing 40 further includes a vertically elongated central hub portion 40e and an outer flange portion 40d. The upper end of central hub portion 40e` defines a socket portion 40e receiving a tapered roller bearing 44. Roller bearing 44 journals the upper end of a vertically oriented drive shaft 46 extending downwardly within center hub portion 40C. A bevel gear 48 is provided at the upper end of vertical drive shaft 46. Bevel gear 48 is interconnected with bevel gear 30 on horizontal drive shaft 26 by a bevel gear 50 journaled on horizontal pivot shaft 38.

Intermediate housing 42 includes an upper hub portion 42a housing a bearing 52 journaling intermediate housing 42 on the central hub portion 40e of upper housing 40. A ring member 54 received in a groove 42d defined by intermediate housing 42 provides a rotary seal between housing 42 and ange portion 40d of housing 40. Housing 42 further includes a lower central hub portion 42c connected to the main body of the housing by a vertical rib 42d and defining at its upper end a socket 42e receiving a bearing 56 journaled on the lower end of hub portion 40e of upper housing 40.

Lower housing 43 defines a central cavity 43a receiving a transmission seen generally at 58. Transmission 58 includes a propeller shaft 60 journaled in a tapered roller bearing 62 received in a socket 64a defined by a bearing block 64 mounted by -bolts 66 in a position plugging the rear end of cavity 43a. The forward end of shaft 60 is journaled in a tapered roller bearing 69 carried by a partition portion 4313 of lower housing 43. Housing 43 also defines a socket 43C for receipt of a tapered roller bearing 68 journaling a bevel gear J70 splined to the lower end of vertical drive shaft 46. Bevel gear 70 engages a forward bevel gear 72 and -a rearward bevel gear 74. A clutching collar 76 carried on a shift rod 78 coaxial with propeller shaft 60 operates in known manner to transmit drive to propeller shaft 60 either through forward bevel 72 or rearward bevel 74. Shift rod 78 is selectively slidable pivotal movement of a bellcrank lever 80 operated by a control rod 82. A propeller 84 is keyed to the distal end of propeller shaft 60.

The operation of the inboard-outboard drive of the invention as thus far described is thought to be readily apparent. Rotation of inboard engine output shaft 26 rotates bevel gear 30 and thereby bevel gears 50 and 48. Gear 48 drives vertical drive shaft 46 and thereby bevel gear 70. Bevel gear 70 drives bevel gears 72 and 74 to transmit either a forward or reverse drive to propeller shaft 60 depending on the position of clutching collar 76. Shifting of transmission 58 between forward and reverse drives is accomplished by reciprocal movement of control rod 82, which movement maybe accomplished either manually or with power assist.

When lower 1in portion 43d of lower housing 43 strikes an obstacle, drive leg 18 is kicked upwardly, pivoting about the axis of pivot shaft 38. During this upward pivotal movement, bevel gear 48 simply rides up on bevel gear 50 so that, although the relative angular positions of the bevel gears are thereby readjusted, the meshing engagement of the bevel gears is not disturbed.

A bevel gear segment 86 is keyed to horizontal pivot shaft 38. Gear 86 engages a bevel gear 88 splined to the rearward end of a horizontal damping shaft 90. Shaft 90 is rotatably received within a cavity 14e in housing 14 and extends horizontally forwardly from bevel gear 88. Shaft 90 is splined intermediate its ends at 90a for splined engagement with a sleeve member 92. A pair of elastomer rings 94 Iare bonded at their inner periphery to the outer periphery of sleeve member 92. The outer peripheries of elastomer members 94 are received with ya frictional sliding fit in a sleeve or socket member 96 journaled in a further cavity 14f of housing 14. Sleeve 96 may be formed of asbestos or other hard, smooth-surfaced material capable of maintaining a fairly constant coefficient of friction over periods of extended usage. The forward end of sleeve 96 is rigidly secured to a worm pinion 98 engaging a worm gear 100 received within :a vertical cavity 14g defined by housing 14. The portion of shaft 90 forward of splined portion 90a passes through the interior of sleeve 92 and through lworm gear 98 for engagement with an elastic stop nut 102; nut 102 precludes `axial movement of worm gear 98 off of shaft 90.

Bevel segment gear 86, bevel gear 88, shaft 90, elastomer members 94 and socket 96 will be seen to provide a mechanism for damping the upward pivotal movement of drive leg 18. Specifically, as drive leg 18 is kicked upwardly upon hitting an obstacle, pivot shaft 38 rotates gear segment 86 which in turn rotates bevel gear 88 and shaft 90. The initial rotary movement of shaft 90 is absorbed by yielding of the elastic material of the elastomer members 94 so that relatively little resistance is offered to such initial movement. Further rotary movement of shaft occurring in response to further upward pivotal movement of the drive leg, exhausts the ability of the elastomer members to yield and causes the elastomer members to break loose at their interface with socket 96 so that such further movement is resisted by the rotary sliding friction between elastomer members 94 and socket 96.

The geared interconnection between horizontal drive shaft 26 and vertical drive shaft 46 is sealed from the water by a flexible bellows-type seal 104 of elastomer material. Seal 104 is clamped to upper drive leg housing 40 by clamping ring 106 and to housing 14 by clamping member 108. Further water sealing protection is afforded to the internal gear mechanisms by an auxiliary housing member 110 suitably secured to housing 14 and extending in an arc centered on the axis of pivot shaft 38 to a ylocation below that shaft. An arcuate slot 112 in auxiliary housing 110 accommodates upward pivotal movement of propulsion unit 18. A plurality of telescopically arranged arcuate vanes 112 pivoted on pins 114 normally close slot 112 but telescope upon themselves to allow drive leg 18 to pivot upwardly into the slot. A tilt adjustment pin 116 received in one of a plurality of holes 11'8 provided in a flange portion 40jc of upper drive leg housing 40 coacts with a snubber-face 14h to selectively adjust the tilt angle or trim of the drive leg.

We claim:

1. In an inboard-outboard drive assembly for a watercraft including an inboard power unit, a drive shaft extending generally horizonally from said power unit rearwardly through the transom of the craft, a propulsion unit disposed outboard of said craft and comprising a drive leg normally depending downwardly to position a propeller carried on the lower end thereof in the water, and means mounting said drive leg for pivotal movement relative to said drive shaft and said craft about a generally horizontal axis to allow said drive leg to pivot upwardly upon striking an underwater object to prevent damage to said assembly; the improvement wherein said mounting means includes (A) a damping shaft;

(B) means operative in response to the aforesaid upward pivotal movement of said drive leg to rotate said damping shaft about its lengthwise axis;

(C) an elastomer member secured to said damping shaft and presenting a cylindrical surface concentric with Said lengthwise shaft axis; and

(D) a normally fixed member presenting a cylindrical surface concentric with said lengthwise shaft axis and telescopically arranged relative to said elastomer member cylindrical surface, said Imembers having a frictional sliding fit at the interface of said surfaces to allow frictionally resisted relative rot-ation of said members so that the elastic material of said elastomer member yields during the initial upward pivotal movement of said drive leg about said horizontal axis, whereafter said members undergo relative rotation at their frictional interface to provide frictional sliding resistance to further upward pivotal movement of said leg.

2. An inboard-outboard drive assembly according to claim 1 wherein (E) said elastomer member comprises a cylindrical sleeve concentrically surrounding, and bonded to, a portion of said damping shaft; and

(F) said normally xed members comprises a cylindrical socket receiving said elastomer sleeve with a tit allowing, but frictionally resisting, rotation of said sleeve within `said socket.

3. An asembly according to claim 1 wherein:

(E) said operative means are also operative to pivot said drive leg upwardly about said horizontal axis in response to rotation of said damping shaft about said lengthwise axis; and

(F) said assembly further includes means for rotating said normally xed member about said lengthwise axis, whereby said drive leg may be pivoted upwardly by selective actuation of said rotating means.

4. An assembly according to claim 1 wherein (E) said damping shaft is disposed generally parallel to said drive shaft; and

(F) said operative means includes a right angle gear connection between said drive leg and said damping shaft.

5. An assembly according to claim 4 wherein (G) said damping shaft extends forwardly through said transom to dispose its forward end within said water craft;

(H) said elastomer member comprises a cylindrical sleeve secured to said forward end of said damping shaft;

(I) said normally xed member comprises a cylindrical socket disposed within said water craft and receiving said elastomer sleeve with a frictional sliding lit; and

(J) said assembly further includes means within said Water craft engaging said socket and operative to selectively rotate it about said damping shaft axis to selectively pivot said drive leg upwardly.

6. An assembly according to claim 5 wherein (K) said assembly further includes a housing secured to the rearward end of said inboard power unit and extending rearwardly therefrom through an opening in said transom, said housing journaling said drive shaft and damping shaft therewithin in side by side relation and adjacent its rearward end journaling said drive leg for its aforesaid pivotal movement about said horizontal axis.

7. An inboard-outboard drive assembly for a water craft comprising (A) an inboard power unit;

(B) a drive shaft extending generally horizontally from said power unit for passage through the transom of said craft;

(C) a propulsion unit disposed outboard of said craft and including a drive leg carrying a propeller on the distal end thereof;

(D) means adapted to be secured to said transom mounting said drive leg for pivotal movement about a generally horizontal axis between a working position in which said leg depends downwardly to dispose said propeller in the water and a raised position in which said leg is pivoted upwardly from its working position;

(E) a drive shaft lying in the plane of said horizontal drive shaft and extending longitudinally of said drive leg for driving connection with said propeller;

(F) gear means drivingly interconnecting said horizontal drive shaft and said drive leg drive shaft and a first bevel gear mounted for rotation on said drive leg pivotal axis, a second bevel gear on the rearward end of said horizontal drive shaft meshingly engaging said first bevel gear, and a third bevel gear on the upper end of said drive leg drive shaft meshingly engaging said first bevel gear;

(G) a fourth bevel gear on said drive leg pivotal axis arranged to be rotated about that axis in response to pivotal movement of said drive leg about that axis;

(H) a damping shaft extending generally parallel to said horizontal drive shaft;

(I) a fth bevel gear on the rearward end of said damping shaft meshingly engaging said fourth bevel gear so that said damping shaft is rotated in response to pivotal movement of said drive leg;

(I) an elastomer member secured to said damping shaft and presenting a cylindrical surface concentric with the lengthwise axis of said damping shaft; and

(K) a normally fixed member presenting a cylindrical surface concentric with said lengthwise shaft axis and telescopically arranged relative to said elastomer member cylindrical surface, said members having a frictional sliding t at the interface of said surfaces to allow frictionally resisted relative rotation of said members so that the elastic material of said elastomer member yields during the initial upward pivotal movement of said drive leg about said horizontal axis, whereafter said members undergo relative rotation at their frictional interface to provide frictional sliding resistance to further upward pivotal movement of said leg.

8. An assembly according to claim 7 wherein said assembly further includes (L) means engaging said normally fixed member and operative to selectively rotate it about said damping shaft axis to selectively pivot said drive leg upwardly.

References Cited UNITED STATES PATENTS 1,384,009 7/ 1921 Borchert. 2,752,875 7/1956 Hills 115-41 3,094,097 6/1963 Ellzey 115--41 3,240,453 3/ 1966 Kiekhaefer 11S-41 X TRYGVE M. BLIX, Primary Examiner. 

